供锌水平对水稻生长和锌保累和分配的影响

通过对3个不同水稻品种（碧玉早糯、26715和浙农921）5个供锌水平（0.0、0.5、2.0、8.0、32.0μmol/L ZnSO4）处理的水培试验，研究供锌水平对水稻生长和锌积累的影响。结果表明，水稻地上部锌含量随供锌水平的提高而提高，不同的供试品种在不同的生育期地上部锌含量的变化趋势存在差别。不同的供试品种之间籽粒锌的积累差异极显著，精米中的锌含量随供锌水平的提高而提高；在8.0、32.0μmol/L Zn水平下，籽粒锌含量差异不大，颖壳锌含量则随供锌水平的提高而提高；≤8.0μmol/L时，精米锌含量比颖壳高，而在高锌水平（32.0μmol/L）下，颖壳的锌含量比精米高。     

水稻籽粒不同部位植酸含量及其与稻米品质的相关性

 选用13个不同类型的水稻品种,对其籽粒不同部位植酸含量品种间差异及与稻米主要品质性状间的相关性进行了分析。结果表明,供试13个水稻品种米糠、糙米、颖壳、精米的植酸含量平均值分别为48.51、9.77、1.40和0.91 mg/g,而且不同水稻品种间籽粒不同部位的植酸含量存在极显著差异。在籽粒中,米糠中植酸积累最多,其次是精米,颖壳最少。米糠中植酸含量与糙米和颖壳中植酸含量呈极显著正相关。糙米和米糠中植酸含量与稻米蛋白质含量均呈显著的负相关,与千粒重均呈显著正相关。     

不同锌效率基因型水稻籽粒中矿质元素的原位微区分布研究

 采用同步辐射（SRXRF）结合ICP MS研究了足Zn条件下不同锌效率水稻籽粒中Zn及其他矿质元素的微区分布特征。结果表明SRXRF技术可高效分析水稻籽粒锌等矿质元素的微区分布特征。水稻籽粒中K和Ca元素的分布特征与其余4种元素相关不显著,而Zn、Fe、Cu、Mn元素的含量分布相互间则显著相关;水稻籽粒中K含量最高,移动性也最强,精米中K含量可达颖壳的52.6%~90.6%,而Ca在颖壳中含量最高。其余矿质元素含量最高值均出现在糊粉层;Zn、Fe等元素主要集中在水稻籽粒的胚及糊粉层等外层功能组织,在胚乳中由外向里呈递减趋势。此外,锌高效基因型IR8192在水稻籽粒各部位的Zn含量均低于锌低效基因型二九丰。可见,与锌低效品种相比,锌高效品种仅在低Zn水平下表现出更高的锌吸能力及利用效率,在足Zn条件下并无籽粒富锌特征。     

汉中地区籼稻锌、铁、锰营养基因型差异及叶面喷锌对籽粒锌含量的影响

分析了参加汉中地区水稻新品种展示的45个籼稻糙米、精米中锌、铁、锰含量的基因型差异。同时进行田间喷施试验,设置喷蒸馏水(CK)、喷Zn、喷Zn+井酮三环唑3个处理,探讨了锌肥与井酮三环唑配施对水稻锌营养品质的影响。结果表明,45个水稻品种糙米中锌、铁、锰的平均含量分别为17.44mg/kg、10.99mg/kg和25.09mg/kg,精米中锌、铁、锰的平均含量分别为11.39mg/kg、4.14mg/kg和7.38mg/kg;糙米中锌、铁、锰含量分别是精米中的1.53倍、2.56倍和3.40倍,即在去糙过程中锌、铁、锰的损失率分别为34.69%、62.33%和70.59%;喷施锌肥有利于水稻产量的提高,同时增加籽粒锌含量。喷Zn、喷Zn+井酮三环唑处理使糙米Zn含量由CK的17.63mg/kg分别提高到22.14mg/kg和21.50mg/kg,增幅分别为25.6%和22.0%,精米Zn含量由CK的10.57mg/kg分别提高到14.08mg/kg和14.79mg/kg,增幅分别为33.2%和40.0%。水稻喷施叶面锌肥与农药后不仅能显著增加稻米锌含量,而且有效预防病虫害。因此,喷施锌肥与喷施农药有机结合有望成为缺锌土壤同时满足籽粒富锌和病虫害防治需求的高效农艺措施。     

叶面施用不同形态锌化合物对稻米锌浓度及有效性的影响

2014年土培条件下,以日本晴、L81和L71为供试材料,开花及花后1周叶面喷施硫酸锌、柠檬酸锌、葡萄糖酸锌和EDTA二钠锌(Zn²⁺浓度均为0.2%,以喷施等量清水为对照),研究叶面喷施不同形态锌化合物对稻穗不同部位糙米锌浓度及有效性的影响。结果表明,稻穗不同部位糙米锌浓度差异显著,其中稻穗上部糙米锌浓度显著大于稻穗中部和下部,植酸、植酸与锌摩尔比则相反,不同处理趋势一致。与不施锌相比,硫酸锌、柠檬酸锌、葡萄糖酸锌和EDTA二钠锌使所有品种糙米锌浓度平均分别增加33%、31%、26%和27%,其中锌处理对稻穗上、中部糙米锌浓度的影响显著大于稻穗下部,供试材料中以日本晴的响应最大。锌处理对糙米植酸浓度影响较小,但对植酸与锌摩尔比影响较大。与对照相比,硫酸锌、柠檬酸锌、葡萄糖酸锌和EDTA二钠锌使所有品种糙米植酸与锌摩尔比平均分别下降25%、24%、22%和18%,其中稻穗上部和中部的降幅大于稻穗下部,日本晴和L71的降幅大于L81;锌处理×品种和锌处理×品种×部位间互作均达显著水平。以上数据说明,水稻籽粒生长早期喷锌处理可大幅增加糙米锌浓度及其生物有效性,增幅因锌化合物、供试品种以及籽粒在稻穗上的着生部位(以强势粒响应更大)而异。     

氮、磷、锌营养对水稻籽粒植酸含量的影响及与几种矿质元素间的相关性

以协青早、秀水110及其辐射诱变获得的低植酸突变系（HIPi1和HIPj1）为材料,通过水培试验对不同氮、磷、锌浓度处理下水稻籽粒植酸含量差异及与几种矿质元素间的相关性进行了比较分析。高水平氮、磷、锌浓度处理的籽粒植酸含量较同一品种的低氮、磷、锌处理均有所降低,但在水稻生育期间,籽粒植酸含量对磷、锌处理浓度变化的敏感性,则因品种的植酸类型特征而异;氮、磷浓度增加能分别提高铁或降低铜在籽粒中的积累,但在高锌处理下,籽粒铁含量明显降低、而钾和镁的含量等却有所升高; 籽粒植酸含量一般与K、Mg、Fe、Cu 4种矿质元素含量呈正相关、与籽粒Zn含量呈负相关,但统计显著水平因品种而异。低植酸突变体籽粒中的K、Mg、Fe、Zn等含量虽略有下降,但可以通过适当的介质营养条件来调节有关矿质营养在水稻籽粒中的积累。     

镉胁迫对不同水稻基因型植株生长和抗氧化酶系统的影响

 以籽粒镉积累水平不同的两种品种（丙97252，低积累型；秀水63，高积累型）为材料，研究了镉胁迫对水稻植株生长和抗氧化酶系统的影响。采用水培试验，镉处理设0.0、0.1、1.0和5.0 μmol/L 4个水平。结果表明，镉胁迫抑制植株生长和叶绿素合成，改变植株丙二醛（MDA）含量和超氧物歧化酶（SOD）、过氧化氢酶（CAT）、过氧化物酶（POD）活性。在抗氧化酶活性上，根和地上部对镉胁迫的反应存在着差异。总体上，SOD、CAT和POD活性随镉水平的提高而减少，而MDA含量则表现相反。根和地上部MDA含量随着培养液中镉浓度提高而增加，且增加幅度秀水63明显大于丙97252。与对照相比，生长在5.0 μmol/L Cd处理下的植株， SOD活性在孕穗期下降46%~52%，在分蘖期仅下降13%~19%。高浓度镉胁迫下，两品种在MDA含量的增加幅度和叶绿素含量的降低幅度上表现不同，显示出它们对镉的耐性存在着差异。     

高产小麦氮素积累及其与产量和蛋白质含量的关系

利用８个高产小麦品种,通过定期取样测定生育期各器官氮素含量,研究其氮素动态变化,进而探讨不同品种各器官氮素含量与产量和蛋白质含量的关系。结果表明,除籽粒外,不同品种各器官的氮素含量均随生育期进程而降低。其中茎秆的降低幅度最大,其次为叶片,再次为根系。叶片、茎秆及颖壳在收获时的含氮量与籽料产量呈负相关,而与籽粒蛋白质含相相关不显著。     

土壤锌素营养及绿肥对水稻锌素营养影响研究进展

分析水稻土锌含量水平现状,综述土壤锌有效性的影响因子和水稻锌的来源,着重阐述绿肥对水稻锌的影响,旨在为以种植紫云英绿肥作为生物强化手段提高湖南省石灰性水稻土地区水稻籽粒锌含量、改善作物和居民锌营养提供科学参考。     

锰-镉互作对水稻生长和植株镉、锰含量的影响

在水培条件下,设置不同水平锰、镉处理,研究了锰对镉胁迫下水稻生长及植株镉、锰、铁、锌含量的影响。在镉胁迫下,正常锰处理(约0.50mg/L)可显著缓解镉对水稻生长的抑制,表现为株高、根长、叶绿素(a、b)含量等参数均高于低锰处理。随着镉处理水平的提高,水稻根系与地上部的镉含量随之上升;在同一镉处理水平下,植株地上部和根系镉含量因培养液中锰水平不同而异:随着锰处理水平的增加,水稻根系中的镉含量下降,而地上部镉含量则显著增加。随着锰、镉处理水平的提高,水稻植株地上部和根系中的铁、锌含量显著下降。此外,还对锰控制水稻镉积累的机理及其利用价值进行了讨论。     

水稻籽粒钾和蛋白质含量的基因型差异

采用对低钾胁迫敏感程度不同的3种水稻基因型进行田间试验, 以研究水稻籽粒中钾和蛋白质含量。结果表明,低钾胁迫降低水稻籽粒中钾含量和粗蛋白含量,谷壳中钾含量高于米粒中钾含量,米粒中钾含量与粗蛋白含量呈显著正相关。钾高效基因型在低钾胁迫下谷壳和米粒中具有较高的钾相对含量,其米粒中的粗蛋白相对含量也较高。     

Effects of Different Nitrogen Fertilizer Levels and Native Soil Properties on Rice Grain Fe, Zn and Protein Contents

Deposition of protein and metal ions (Fe, Zn) in rice grains is a complex polygenic trait showing considerable environmental effect. To analyze the effect of nitrogen application levels and native soil properties on rice grain protein, iron (Fe) and zinc (Zn) contents, 32 rice genotypes were grown at three different locations each under 80 and 120 kg/hm2 nitrogen fertilizer applications. In treatments with nitrogen fertilizer application, the brown rice grain protein content (GPC) increased significantly (1.1% to 7.0%) under higher nitrogen fertilizer application (120 kg/hm2) whereas grain Fe/Zn contents showed non-significant effect of nitrogen application level, thus suggesting that the rate of uptake and translocation of macro-elements does not influence the uptake and translocation of micro-elements. The pH, organic matter content and inherent Fe/Zn levels of native soil showed significant effects on grain Fe and Zn contents of all the rice genotypes. Grain Zn content of almost all the tested rice genotypes was found to increase at Location III having loamy soil texture, neutral pH value (pH 6.83) and higher organic matter content than the other two locations (Locations I and II), indicating significant influence of native soil properties on brown rice grain Zn content while grain Fe content showed significant genotype × environment interaction effect. Genotypic difference was found to be the most significant factor to affect grain Fe/Zn contents in all the tested rice genotypes, indicating that although native soil properties influence phyto-availability of micronutrients and consequently influencing absorption, translocation and grain deposition of Fe/Zn ions, yet genetic makeup of a plant determines its response to varied soil conditions and other external factors. Two indica rice genotypes R-RF-31 (27.62 μg/g grain Zn content and 7.80% GPC) and R1033-968-2-1 (30.05 μg/g grain Zn content and 8.47% GPC) were identified as high grain Zn and moderate GPC rice genotypes. These results indicate that soil property and organic matter content increase the availability of Fe and Zn in rhizosphere, which in turn enhances the uptake, translocation and redistribution of Fe/Zn into rice grains.     

Variations in Concentration and Distribution of Health-Related Elements Affected by Environmental and Genotypic Differences in Rice Grains

Malnutrition is one of the major problems inmost of the developing countries, especially amongwomen, infants and children. Biofortification is a verynew strategy to enhance the bioavailability ofmicronutrients in staple food by using advancedbreeding meth…     

Distribution of phytic acid and mineral elements in three indica rice (Oryza sativa L.) cultivars

Three indica rice cultivars with different grain shapes were selected to determine the milling characteristics and distribution of phytic acid (PA) and six mineral elements including magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), zinc (Zn), and selenium (Se). Milling characteristics were quite different among the rice cultivars with different physical dimensions. Similar milling times did not necessarily result in the same degree of milling (DOM) for different rice cultivars. The concentrations of phytic acid and minerals decreased with an increased DOM. These results also showed that phytic acid and minerals except for Zn and Se were not evenly distributed and highly concentrated in the outer layer (0% < DOM < 15%) of the rice kernel. In contrast, Zn and Se seem to be relatively evenly distributed in the grain. Optimum DOM of about 14% was detected for Zhenong 7 (long and slender grain); 10% was found for Zhenong 60 (medium-grain) and 9% for Zhenong 34 (short and round grain). The information generated in this experiment could be useful to optimize milling procedures for maximum removal of phytic acid, minimum mineral losses and weight loss in indica rice cultivars with different grain shapes.     

水稻锌营养高效基因型的生理特性

采用HEDTA螯合缓冲营养液培养法,研究了水稻锌营养高效基因型IR34、IR36、IR8192和锌敏感基因型IR26、测64 7、碧玉早糯在不同锌离子活度（pZn2+>11.5,11.3, 11.0, 10.6, 10.3, 9.7）下的生理特性。结果表明,锌离子活度在对不同水稻基因型秧苗生理特性影响上有明显的区别,其中叶绿素含量、光合速率、MDA含量和根系H+分泌量差异比较明显。在供锌水平较低情况下,水稻锌营养高效基因型叶绿素含量下降速度慢,光合速率降低幅度小,MDA含量升高的幅度小,根系能分泌更多的H+,这些指标可以作为衡量水稻锌营养效率的指标。     

Dry Matter Partitioning and Harvest Index Differ in Rice Genotypes with Variable Rates of Phosphorus and Zinc Nutrition

Phosphorus(P) and zinc(Zn) deficiencies are the major problems that decrease crop productivity under rice-wheat cropping system. Field experiments were conducted to investigate impacts of P(0, 40, 80 and 120 kg/hm~2) and Zn levels(0, 5, 10 and 15 kg/hm~2) on dry matter(DM) accumulation and partitioning, and harvest index of three rice genotypes ‘fine(Bamati-385) vs. coarse(F-Malakand and Pukhraj)' at various growth stages(tillering, heading and physiological maturity). The experiments were conducted at farmers' field at Batkhela in Northwestern Pakistan for two years in summer 2011 and 2012. The two year pooled data reveled that there were no differences in percent of DM partitioning into leaves and culms with application of different P and Zn levels, and genotypes at tillering. The highest P level(120 kg/hm~2) partitioned more DM into panicles than leaves and culms at heading and physiological maturity stages. The highest Zn level(15 kg/hm~2) accumulated more DM and partitioned more DM into panicles than leaves and culms at heading and physiological maturity stages. The hybrid rice(Pukhraj) produced and partitioned more DM into panicles than F-Malakand and Bamati-385 at heading and physiological maturity stages. Higher DM accumulation and greater amounts of partitioning into panicles at heading and physiological maturity stages was noticed with increase in P and Zn levels, and the increase was significantly higher in the coarse rice genotypes than fine. We concluded that the growing hybrid rice with application of 120 kg/hm~2 P + 15 kg/hm~2 Zn not only increases total DM accumulation and partitioned greater amounts into the reproductive plant parts(panicles) but also results in higher harvest index.     

Response of Iron Content in Milled Rice to Nitrogen Levels and Its Genotypic Differences

To investigate the effect of nitrogen (N) level on iron (Fe) content in milled rice, a field experiment was carried out under three N application levels including 0, 150 and 300 kg/hm² by using 120 rice genotypes. In addition to the genotypic differences of iron content in milled rice, grain yield, 1000-grain weight and N content in grains under the same N level, there were also variations in the response of Fe content in milled rice to N levels. Based on the range and variation coefficient of Fe content in milled rice under the three N levels, the response of Fe content in milled rice to N levels could be classified into four types including highly insensitive, insensitive, sensitive and highly sensitive types. A significant quadratic correlation was found between the Fe content in milled rice and 1000-grain weight or the N content in grains. However, no significant correlation between the Fe content in milled rice and grain yield was detected. In conclusion, there are genotypic differences in the effects of N levels on Fe content in milled rice, which is favorable to breeding of Fe-rich rice under different N environments. Furthermore, high yield and Fe-rich rice could be grown through the regulation of nitrogen on Fe content in milled rice, 1000-grain weight and N content in milled rice.     

施氮处理对水稻精米中铁含量的影响及基因型差异

以120份国内外水稻基因型为材料,设置0、150、300kg/hm23个氮素水平,研究施氮处理对水稻精米中Fe含量的影响及其基因型差异。除相同氮素条件下水稻精米中的Fe含量、产量、千粒重及籽粒含氮量存在基因型差异外,精米中的Fe含量对氮素反应的敏感性也存在显著差异。以各基因型水稻在不同氮素条件下精米中Fe含量的极差和变异系数为指标,通过系统聚类的方法,可将上述120份水稻基因型对氮素反应的敏感性分为极钝感型、钝感型、敏感型和极敏感型共4种类型。同时,相关性分析表明,水稻精米中的Fe含量与产量的相关性不显著,而与粒重、籽粒含氮量呈显著或极显著的二次曲线关系。由此说明,施氮处理对水稻精米中Fe含量的影响具有基因型差异,充分利用这种差异一方面有利于对氮环境适应性强的富铁水稻的选育;另一方面,由于精米中的Fe含量与产量无必然联系,可通过氮肥对水稻(尤其是敏感和极敏感类型水稻)精米中的Fe含量和粒重、籽粒含氮量的调节,实现富铁、高产水稻的种植。